Clearly you are trying to find the answers yourself! That's good. I can tell you a few things from my own experience--others will likely come along and make recommendations, too. I don't immediately find much when I google stretch hexayurts eplaya
though. I've seen one stretch hexayurt at the event that I can remember--it's not something I look for--but foam panels seem to be much more common, and I see them everywhere.
I have a tent tall enough to stand in (Guide Gear Single Pole Wigwam). 10" Coleman stakes. It is not
3-room; just one. Larger, double pole versions are made, though. I camped next to one in 2010. My single-pole wigwam will fit a queen mattress (which I have tried on a regular camping trip), although it takes up half the floor space if I do, & touches the center pole. I like a lot of space in my tent & I sleep alone out there, so I use a single cot instead (& the space under the cot for storage, which is really handy).
The Wigwam has withstood winds in 2009, 2010, 2011 and 2012, although none of these years gave it the test that 2008 would've. My previous tent, a simple dome, survived crazy
-windy 2008 with excellent staking, & the mild shield of a van parked south of it, but not terribly close--which would've been better. (I also used domes in 2000 and 2001 with a fair amount of wind. I remember a 4 hour Wednesday storm in 2000. Good staking and good luck prevailed).
In 2009 and 2010 the wigwam had no vehicle shielding, & withstood moderate wind/rain, but nothing extreme.
In 2011 an RV was parked 8 feet South of my wigwam, & it did fine. However, the weather was the best it's ever been.
In 2012 I pitched the wigwam in a corner between 2 RVs forming an "L" (one aimed [approximately] East-West, one North-South). This was wonderful, and gave me quite a bit of protection, although the wind last year was very mild. Better yet: I got an extra hour of sleep in the morning. I will totally do this again if I can. (I don't shade my tent, I like to leave my tent and sit in my shade.)
In summary: RVs are excellent tent protection, but serious staking--and use of any vehicle as a windblock--goes a long way.
Shade that doesn't collapse or blow away is harder to achieve than tents that won't.
Prevailing winds are from the SW.